Uterine fibroid, also called leiomyomas, is the most common tumor in women, affecting more than 70% of women over the age of 50. As a generally benign disease, the uterine fibroid can potentially contribute to female stroke through different pathological conditions. The relationship between uterine fibroids and stroke was occasionally reported in sporadic case reports. However, fibroids-related stroke still remains elusive at the population level. This study conducted Mendelian randomization (MR) analysis to investigate the risk of stroke (outcome) following uterine fibroid (exposure). Furthermore, through interrogating the largest clinically representative cohort of 521,612 participants, this study had sufficient power to detect the causality of uterine fibroid on different stroke subtypes, thus discovering the small vessel ischemic stroke (IS) as the most significant stroke subtype associated with uterine fibroids. In conclusion, this study explicitly indicates that uterine fibroids can causally increase the risk of stroke, rather than just a benign disease. This finding strongly suggests the importance of encompassing female populations in stroke studies and the investigation of fibroid-related stroke as a novel stroke subtype from animal models through clinical trials.

The authors have declared no competing interest.

This project was supported by the National Natural Science Foundation of China (32100739) to Dr. Ming Zheng. All funding sources have been identified, and no additional funding was received for this study.

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Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

No human subjects were directly involved in this study. All the data used in this study was derived from existing de-identified biological samples from prior studies. Thus, ethical and patient consent was not required in this study.

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Yes

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All data produced in the present study are available upon reasonable request to the authors.